A variety of different building techniques and materials are employed for the construction of residential and commercial small building types. A majority of these buildings, however, are constructed by means of light frame wood construction. Conventional light frame construction involves piece-by-piece on-site cutting, fitting, and assembly of the different parts of the building comprising the exterior and interior walls, ceiling and roof members. This is a labor-intensive operation which requires a high degree of carpentry skills. It is necessary to coordinate the carpentry work with that of other trades such as plumbing, heating and electrical, on a relatively precise and critical time schedule. Because so much work must be done on a piece-by-piece basis at the site, a considerable time lapse occurs between the start of the work and the point where the house or building finally is enclosed and is relatively immune from wind and rain during the remainder of the construction of the interior. In such conventional frame construction, holes must be cut or drilled in the framing for electric lines, plumbing pipes and some duct work. All of this is time consuming and expensive, and adds considerably to the completed cost of the building.
In efforts to reduce the amount of building time on the site of construction, and further, to provide a less expensive but structurally stronger building, proposals have been made for what may be termed "truss-frame" houses. Such a construction technique is disclosed in the patent to Roger L. Tuomi, U.S. Pat. No. 4,005,556. The structure of this patent consists of a plurality of flat structural building frames, each comprising a roof truss system and a floor truss system interconnected at opposite ends to one another through conventional wall studs. The floor truss system is necessary to provide structural rigidity to the overall unit, so that the resultant frame comprises a completely enclosed outline of the building envelope ultimately to be enclosed by it. These frames then are set up side by side on the building foundation and are interconnected to give them vertical stability. The siding, flooring and roof sheathing is attached to the frames in a conventional manner. The use of the structures disclosed in the Tuomi patent considerably reduces the time required to erect and enclose a house or other building. The floor truss arrangement and the roof truss system both provide spaces for the major plumbing, electrical and ductwork required in the building. It still is necessary, however, to drill or cut holes in the studs forming the exterior walls to accomodate electrical lines, plumbing and the like in these walls. In addition, it should be noted that the structure of the Tuomi patent is not suited for houses of the type constructed on poured concrete slabs which do not have basements or crawl spaces beneath the main floor. Such construction, however, is widely used, particularly in the southern and western parts of the United Stats. Consequently, the Tuomi interconnected roof truss/floor truss system does not have utility where slab floor construction is desired.
Another system using components which are similar to the ones used in the Tuomi patent is disclosed in the patent to Slayter, U.S. Pat. No. 3,156,018. The Slayter patent is directed to a plant-manufactured building structure or a prefabricated complete building structure. Subcomponents of this building structure include roof and floor truss subsystems which are interconnected by a sidewall system of a generally triangular configuration. This produces outwardly sloped exterior sidewalls with a vertical inside sidewall surface. The Slater system requires a complete surrounding truss subsystem including floor, roof and the interconnecting sidewall system. These are all incorporated together into a prefabricated building which subsequently is moved from the manufacturing site to the site where it is to be erected.
In the construction of commercial building using metal or steel truss systems and reinforced steel sidewall systems, various attempts have been made to prefabricate subsystems for subsequent interconnection and erection at the building site. One such system is shown in the patent to Ollman, U.S. Pat. No. 4,030,256. This patent discloses the use of a steel roof and ceiling system using prefabricated roof and ceiling truss frames. Each of these has downwardly depending vertical legs at the corners which then subsequently are connected to sidewall steel frame subsections to construct a completed building. Thus, separate matching sections must be aligned and interconnected at the building site in order to produce the frame for the building constructed in accordance with the building construction system disclosed in the Ollman patent.
Other patents have disclosed building subsystems utilizing metal or wooden trusses formed in generally L-shaped configurations to produce wall and roof subsections, two of which are interconnected together at the building site at the apex of the roof sections to form the frame for enclosing the building. These systems generally are used for warehouses and the like, and the nature of the trusses generally is in the form of triangular legs of non-uniform depth which precludes their use in most homes and small office buildings. In addition, it still is necessary in the construction of buildings using such systems to cut or drill holes for plumbing, electrical lines or ductwork necessary for the completed building structure. Three patents which disclose systems of this type are the patents to Prudhon, U.S. Pat. No. 2,904,139; Sahlberg, U.S. Pat. No. 2,390,180; and Dickinson, U.S. Pat. No. 3,263,381.
Various other preassembled building structures have been attempted in the past, but all are subject to one or more shortcomings present in the structures discussed above. Generally, these subsystems are not such as to substantially minimize the construction work required at the building site. Most of them do not facilitate the installation of wiring, heating and plumbing lines, but generally are subject to the same disadvantages encountered in conventional on-site frame construction of buildings.
Accordingly, it is an object of this invention to provide an improved building system which is capable of reducing the cost of the completed building, simplifies the construction, and provides a variety of possibilities for architectural variations from both aesthetic and practical considerations resulting directly from the building subsystem itself.